Maintenance of Glutathione Levels in Renal Cortex Slices of the Rat

Abstract

The level of reduced glutathione (GSH) in renal cortex slices was a function of overall metabolism and availability of the component amino acids of GSH. Incubation of slices in oxygenated Krebs-Ringer media at 37.degree. C resulted in a steady loss of GSH. Nearly 50% of the initial GSH was lost in 1 h. This loss was offset when the incubation was carried out a reduced temperature. Anaerobic conditions or incubation with dinitrophenol enhanced the disappearance of GSH. Fortification of the medium with glycine and glutamic acid at 3 mM concentration each or glycine, glutamic acid and cysteine each at 0.1 mM resulted in a marked increase of GSH levels after 60 min incubation compared to unfortified slices. Dithiothreitol enhanced the effect of cysteine, but had no significant effect on its own. The presence of 4% (wt/vol) bovine serum albumin in the medium had no effect on loss of GSH. Disodium maleate had no effect for up to 1 h of incubation and produced only slight additional loss of GSH after 1.5 and 2.0 h of incubation.